More problems for McLaren

Honda decided to change the engine in the car Stoffel Vandoorne was driving when they discovered an electrical problem after just 34 laps.

It is the latest in a series of problems with Honda’s newly redesigned engine.

Honda has had three engine failures in the course of five days of testing so far. The Japanese company has not revealed how many engines it has gone through – a spokesman saying it has used “a mixture, and some have been used on multiple days” – but it is believed to be at least five.

Vandoorne ended the day 10th fastest, 2.8secs off the pace.

McLaren racing director Eric Boullier admitted relations between the two partners were under “maximum” strain.

He added: “The pressure is obviously huge and obviously we put the maximum pressure on all of our relationship with Honda, and the same for them.

“We cannot put a footstep wrong. We need to be able to deliver the best car as well, so this is both sides.”

He said he hoped a new specification of Honda engine to be introduced before the end of this week’s test would solve “part of this problem – or most of this problem”.

And he insisted McLaren were not considering ending its contract with Honda, which is in the third of 10 years.

“We have a contract in place,” said Boullier. “We don’t even obviously think about it, because there is a contract between us, a long term contract, and we want to build on it even if it is not ideal times.”